35
Operation and Maintenance Manual
QTS Series Twin Screw Positive Displacement Pump
QTS-M04
M
A
INTE
N
A
N
C
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Important Notes
1. Use a six points female socket preferably to loosen and tighten the front cover nuts to prevent
marking them.
2. The wet parts comprises the front cover (
1
), rotor nut (
11
), rotors (
2
,
3
), pump casing (
4
), mechanical
seals (
12
) and the back cover (
5
). Check that these components are free from damage such as hit
marks, abrasion from fluids, or any deformation caused by foreign objects. If considerable damage
exists and the pump efficiency is reduced, contact your distributor for spare parts.
Be aware that
any damage in the casing or rotors can cause pump malfunctioning due to its small clearances.
3. If any of the gaskets or O-rings are damaged (marks, wear or deformation) replace them all
together; use a replacement kit for gaskets and O-rings of the same material according to the
pump application (either EPDM or Viton).
4. All gasket grooves must remain intact; otherwise the presence of hits or marks may result in leakage.
5. Always use a six points female socket to loosen and tighten the rotor nuts to avoid indentations.
6. The dowel pins surface finish is rectified. If they are damaged, replace them to prevent assembly
problems.
7. Synchronization or rotor assembly is incorrect if rubbing marks are shown between the rotors. So
if its necessary to replace rotors also it is necessary to repeat the gear synchronization procedure.
Please contact Q-Pumps for instructions.
8. Single mechanical seal housing (
12J
) has only one external groove while the double mechanical
seal housing (
12U
) has two external grooves.
9. You may use water or a FDA food grade silicon base lubricant to lubricate O-rings and gaskets.
10. When an O-ring is damaged, it is highly recommended to replace the entire set of O-rings
(including both shafts) at the same time to ensure the service life.
11. The seal faces are very fragile, handle and place them with care to avoid breaking or loosing.
12. If any seal face is scratched, hit or damaged, it is highly recommended to replace the entire
seal kit to ensure the service life.
13. Ensure that the drag pins match the notches on the seal elements for the right position
and assembly.
14. Every double mechanical seals without exception should be properly lubricated. Even the
shortest time operating without lubrication may damage the mechanical seals. The flush system
must be installed before starting the pump.